DESCRIPTION: Research has shown that cognitive therapy (CT) is one of the most effective treatments for depression. However, surprisingly little is known about the processes of change during, and after, a course of treatment with CT or about what factors, both specific and nonspecific to CT, are associated with such change. The proposed research will examine two potentially important factors in the change process: acquisition and application of cognitive skills taught in CT, and social-cognitive changes. Few published studies have considered the specific issues involved in measuring these potentially significant processes. No adequately standardized measures of skill acquisition/mastery in CT are currently available. Furthermore, the measures that have been used previously to assess CT skill acquisition are vulnerable to demand characteristics. The proposed research will compare several methods for assessing skill acquisition and application and will contrast those indices to two well-established measures of social-cognitive style (need for cognition and integrative complexity). Individuals with major depression will be randomly assigned to 3 conditions: CT, self-regulation therapy SRT), or pharmacotherapy. A battery of questionnaires will be administered at pre- and post-treatment and at a 6-month follow-up, including measures of depression and other psychological symptoms, use of different types of coping skills (including cognitive strategies), and cognitive content, such as beliefs and attitudes. Several proposed measures of skill acquisition and application also will be administered. Specific hypotheses about the expected role of skill acquisition and social cognition in relation to outcome are formulated and tested.